Merge branch 'for-davem' of git://git.infradead.org/users/linville/wireless-next
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / stat.c
blob78a3aa83c7eac3f153cc5e370cabd754babb9aab
1 /*
2 * linux/fs/stat.c
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
7 #include <linux/module.h>
8 #include <linux/mm.h>
9 #include <linux/errno.h>
10 #include <linux/file.h>
11 #include <linux/highuid.h>
12 #include <linux/fs.h>
13 #include <linux/namei.h>
14 #include <linux/security.h>
15 #include <linux/syscalls.h>
16 #include <linux/pagemap.h>
18 #include <asm/uaccess.h>
19 #include <asm/unistd.h>
21 void generic_fillattr(struct inode *inode, struct kstat *stat)
23 stat->dev = inode->i_sb->s_dev;
24 stat->ino = inode->i_ino;
25 stat->mode = inode->i_mode;
26 stat->nlink = inode->i_nlink;
27 stat->uid = inode->i_uid;
28 stat->gid = inode->i_gid;
29 stat->rdev = inode->i_rdev;
30 stat->size = i_size_read(inode);
31 stat->atime = inode->i_atime;
32 stat->mtime = inode->i_mtime;
33 stat->ctime = inode->i_ctime;
34 stat->blksize = (1 << inode->i_blkbits);
35 stat->blocks = inode->i_blocks;
38 EXPORT_SYMBOL(generic_fillattr);
40 int vfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
42 struct inode *inode = dentry->d_inode;
43 int retval;
45 retval = security_inode_getattr(mnt, dentry);
46 if (retval)
47 return retval;
49 if (inode->i_op->getattr)
50 return inode->i_op->getattr(mnt, dentry, stat);
52 generic_fillattr(inode, stat);
53 return 0;
56 EXPORT_SYMBOL(vfs_getattr);
58 int vfs_fstat(unsigned int fd, struct kstat *stat)
60 struct file *f = fget(fd);
61 int error = -EBADF;
63 if (f) {
64 error = vfs_getattr(f->f_path.mnt, f->f_path.dentry, stat);
65 fput(f);
67 return error;
69 EXPORT_SYMBOL(vfs_fstat);
71 int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
72 int flag)
74 struct path path;
75 int error = -EINVAL;
76 int lookup_flags = 0;
78 if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
79 AT_EMPTY_PATH)) != 0)
80 goto out;
82 if (!(flag & AT_SYMLINK_NOFOLLOW))
83 lookup_flags |= LOOKUP_FOLLOW;
84 if (flag & AT_EMPTY_PATH)
85 lookup_flags |= LOOKUP_EMPTY;
87 error = user_path_at(dfd, filename, lookup_flags, &path);
88 if (error)
89 goto out;
91 error = vfs_getattr(path.mnt, path.dentry, stat);
92 path_put(&path);
93 out:
94 return error;
96 EXPORT_SYMBOL(vfs_fstatat);
98 int vfs_stat(const char __user *name, struct kstat *stat)
100 return vfs_fstatat(AT_FDCWD, name, stat, 0);
102 EXPORT_SYMBOL(vfs_stat);
104 int vfs_lstat(const char __user *name, struct kstat *stat)
106 return vfs_fstatat(AT_FDCWD, name, stat, AT_SYMLINK_NOFOLLOW);
108 EXPORT_SYMBOL(vfs_lstat);
111 #ifdef __ARCH_WANT_OLD_STAT
114 * For backward compatibility? Maybe this should be moved
115 * into arch/i386 instead?
117 static int cp_old_stat(struct kstat *stat, struct __old_kernel_stat __user * statbuf)
119 static int warncount = 5;
120 struct __old_kernel_stat tmp;
122 if (warncount > 0) {
123 warncount--;
124 printk(KERN_WARNING "VFS: Warning: %s using old stat() call. Recompile your binary.\n",
125 current->comm);
126 } else if (warncount < 0) {
127 /* it's laughable, but... */
128 warncount = 0;
131 memset(&tmp, 0, sizeof(struct __old_kernel_stat));
132 tmp.st_dev = old_encode_dev(stat->dev);
133 tmp.st_ino = stat->ino;
134 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
135 return -EOVERFLOW;
136 tmp.st_mode = stat->mode;
137 tmp.st_nlink = stat->nlink;
138 if (tmp.st_nlink != stat->nlink)
139 return -EOVERFLOW;
140 SET_UID(tmp.st_uid, stat->uid);
141 SET_GID(tmp.st_gid, stat->gid);
142 tmp.st_rdev = old_encode_dev(stat->rdev);
143 #if BITS_PER_LONG == 32
144 if (stat->size > MAX_NON_LFS)
145 return -EOVERFLOW;
146 #endif
147 tmp.st_size = stat->size;
148 tmp.st_atime = stat->atime.tv_sec;
149 tmp.st_mtime = stat->mtime.tv_sec;
150 tmp.st_ctime = stat->ctime.tv_sec;
151 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
154 SYSCALL_DEFINE2(stat, const char __user *, filename,
155 struct __old_kernel_stat __user *, statbuf)
157 struct kstat stat;
158 int error;
160 error = vfs_stat(filename, &stat);
161 if (error)
162 return error;
164 return cp_old_stat(&stat, statbuf);
167 SYSCALL_DEFINE2(lstat, const char __user *, filename,
168 struct __old_kernel_stat __user *, statbuf)
170 struct kstat stat;
171 int error;
173 error = vfs_lstat(filename, &stat);
174 if (error)
175 return error;
177 return cp_old_stat(&stat, statbuf);
180 SYSCALL_DEFINE2(fstat, unsigned int, fd, struct __old_kernel_stat __user *, statbuf)
182 struct kstat stat;
183 int error = vfs_fstat(fd, &stat);
185 if (!error)
186 error = cp_old_stat(&stat, statbuf);
188 return error;
191 #endif /* __ARCH_WANT_OLD_STAT */
193 static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
195 struct stat tmp;
197 #if BITS_PER_LONG == 32
198 if (!old_valid_dev(stat->dev) || !old_valid_dev(stat->rdev))
199 return -EOVERFLOW;
200 #else
201 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
202 return -EOVERFLOW;
203 #endif
205 memset(&tmp, 0, sizeof(tmp));
206 #if BITS_PER_LONG == 32
207 tmp.st_dev = old_encode_dev(stat->dev);
208 #else
209 tmp.st_dev = new_encode_dev(stat->dev);
210 #endif
211 tmp.st_ino = stat->ino;
212 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
213 return -EOVERFLOW;
214 tmp.st_mode = stat->mode;
215 tmp.st_nlink = stat->nlink;
216 if (tmp.st_nlink != stat->nlink)
217 return -EOVERFLOW;
218 SET_UID(tmp.st_uid, stat->uid);
219 SET_GID(tmp.st_gid, stat->gid);
220 #if BITS_PER_LONG == 32
221 tmp.st_rdev = old_encode_dev(stat->rdev);
222 #else
223 tmp.st_rdev = new_encode_dev(stat->rdev);
224 #endif
225 #if BITS_PER_LONG == 32
226 if (stat->size > MAX_NON_LFS)
227 return -EOVERFLOW;
228 #endif
229 tmp.st_size = stat->size;
230 tmp.st_atime = stat->atime.tv_sec;
231 tmp.st_mtime = stat->mtime.tv_sec;
232 tmp.st_ctime = stat->ctime.tv_sec;
233 #ifdef STAT_HAVE_NSEC
234 tmp.st_atime_nsec = stat->atime.tv_nsec;
235 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
236 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
237 #endif
238 tmp.st_blocks = stat->blocks;
239 tmp.st_blksize = stat->blksize;
240 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
243 SYSCALL_DEFINE2(newstat, const char __user *, filename,
244 struct stat __user *, statbuf)
246 struct kstat stat;
247 int error = vfs_stat(filename, &stat);
249 if (error)
250 return error;
251 return cp_new_stat(&stat, statbuf);
254 SYSCALL_DEFINE2(newlstat, const char __user *, filename,
255 struct stat __user *, statbuf)
257 struct kstat stat;
258 int error;
260 error = vfs_lstat(filename, &stat);
261 if (error)
262 return error;
264 return cp_new_stat(&stat, statbuf);
267 #if !defined(__ARCH_WANT_STAT64) || defined(__ARCH_WANT_SYS_NEWFSTATAT)
268 SYSCALL_DEFINE4(newfstatat, int, dfd, const char __user *, filename,
269 struct stat __user *, statbuf, int, flag)
271 struct kstat stat;
272 int error;
274 error = vfs_fstatat(dfd, filename, &stat, flag);
275 if (error)
276 return error;
277 return cp_new_stat(&stat, statbuf);
279 #endif
281 SYSCALL_DEFINE2(newfstat, unsigned int, fd, struct stat __user *, statbuf)
283 struct kstat stat;
284 int error = vfs_fstat(fd, &stat);
286 if (!error)
287 error = cp_new_stat(&stat, statbuf);
289 return error;
292 SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
293 char __user *, buf, int, bufsiz)
295 struct path path;
296 int error;
298 if (bufsiz <= 0)
299 return -EINVAL;
301 error = user_path_at(dfd, pathname, LOOKUP_EMPTY, &path);
302 if (!error) {
303 struct inode *inode = path.dentry->d_inode;
305 error = -EINVAL;
306 if (inode->i_op->readlink) {
307 error = security_inode_readlink(path.dentry);
308 if (!error) {
309 touch_atime(path.mnt, path.dentry);
310 error = inode->i_op->readlink(path.dentry,
311 buf, bufsiz);
314 path_put(&path);
316 return error;
319 SYSCALL_DEFINE3(readlink, const char __user *, path, char __user *, buf,
320 int, bufsiz)
322 return sys_readlinkat(AT_FDCWD, path, buf, bufsiz);
326 /* ---------- LFS-64 ----------- */
327 #ifdef __ARCH_WANT_STAT64
329 static long cp_new_stat64(struct kstat *stat, struct stat64 __user *statbuf)
331 struct stat64 tmp;
333 memset(&tmp, 0, sizeof(struct stat64));
334 #ifdef CONFIG_MIPS
335 /* mips has weird padding, so we don't get 64 bits there */
336 if (!new_valid_dev(stat->dev) || !new_valid_dev(stat->rdev))
337 return -EOVERFLOW;
338 tmp.st_dev = new_encode_dev(stat->dev);
339 tmp.st_rdev = new_encode_dev(stat->rdev);
340 #else
341 tmp.st_dev = huge_encode_dev(stat->dev);
342 tmp.st_rdev = huge_encode_dev(stat->rdev);
343 #endif
344 tmp.st_ino = stat->ino;
345 if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
346 return -EOVERFLOW;
347 #ifdef STAT64_HAS_BROKEN_ST_INO
348 tmp.__st_ino = stat->ino;
349 #endif
350 tmp.st_mode = stat->mode;
351 tmp.st_nlink = stat->nlink;
352 tmp.st_uid = stat->uid;
353 tmp.st_gid = stat->gid;
354 tmp.st_atime = stat->atime.tv_sec;
355 tmp.st_atime_nsec = stat->atime.tv_nsec;
356 tmp.st_mtime = stat->mtime.tv_sec;
357 tmp.st_mtime_nsec = stat->mtime.tv_nsec;
358 tmp.st_ctime = stat->ctime.tv_sec;
359 tmp.st_ctime_nsec = stat->ctime.tv_nsec;
360 tmp.st_size = stat->size;
361 tmp.st_blocks = stat->blocks;
362 tmp.st_blksize = stat->blksize;
363 return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
366 SYSCALL_DEFINE2(stat64, const char __user *, filename,
367 struct stat64 __user *, statbuf)
369 struct kstat stat;
370 int error = vfs_stat(filename, &stat);
372 if (!error)
373 error = cp_new_stat64(&stat, statbuf);
375 return error;
378 SYSCALL_DEFINE2(lstat64, const char __user *, filename,
379 struct stat64 __user *, statbuf)
381 struct kstat stat;
382 int error = vfs_lstat(filename, &stat);
384 if (!error)
385 error = cp_new_stat64(&stat, statbuf);
387 return error;
390 SYSCALL_DEFINE2(fstat64, unsigned long, fd, struct stat64 __user *, statbuf)
392 struct kstat stat;
393 int error = vfs_fstat(fd, &stat);
395 if (!error)
396 error = cp_new_stat64(&stat, statbuf);
398 return error;
401 SYSCALL_DEFINE4(fstatat64, int, dfd, const char __user *, filename,
402 struct stat64 __user *, statbuf, int, flag)
404 struct kstat stat;
405 int error;
407 error = vfs_fstatat(dfd, filename, &stat, flag);
408 if (error)
409 return error;
410 return cp_new_stat64(&stat, statbuf);
412 #endif /* __ARCH_WANT_STAT64 */
414 /* Caller is here responsible for sufficient locking (ie. inode->i_lock) */
415 void __inode_add_bytes(struct inode *inode, loff_t bytes)
417 inode->i_blocks += bytes >> 9;
418 bytes &= 511;
419 inode->i_bytes += bytes;
420 if (inode->i_bytes >= 512) {
421 inode->i_blocks++;
422 inode->i_bytes -= 512;
426 void inode_add_bytes(struct inode *inode, loff_t bytes)
428 spin_lock(&inode->i_lock);
429 __inode_add_bytes(inode, bytes);
430 spin_unlock(&inode->i_lock);
433 EXPORT_SYMBOL(inode_add_bytes);
435 void inode_sub_bytes(struct inode *inode, loff_t bytes)
437 spin_lock(&inode->i_lock);
438 inode->i_blocks -= bytes >> 9;
439 bytes &= 511;
440 if (inode->i_bytes < bytes) {
441 inode->i_blocks--;
442 inode->i_bytes += 512;
444 inode->i_bytes -= bytes;
445 spin_unlock(&inode->i_lock);
448 EXPORT_SYMBOL(inode_sub_bytes);
450 loff_t inode_get_bytes(struct inode *inode)
452 loff_t ret;
454 spin_lock(&inode->i_lock);
455 ret = (((loff_t)inode->i_blocks) << 9) + inode->i_bytes;
456 spin_unlock(&inode->i_lock);
457 return ret;
460 EXPORT_SYMBOL(inode_get_bytes);
462 void inode_set_bytes(struct inode *inode, loff_t bytes)
464 /* Caller is here responsible for sufficient locking
465 * (ie. inode->i_lock) */
466 inode->i_blocks = bytes >> 9;
467 inode->i_bytes = bytes & 511;
470 EXPORT_SYMBOL(inode_set_bytes);